Traveling wave tubes (TWT) or traveling wave tube amplifiers (TWTA) are used to amplify electric signals. They achieve high amplification factors and may deliver high power. Due to this reason, traveling wave tube amplifiers are often used as part of communication links, e.g. satellite radio signaling links, or also as part of radar systems as to generate and send out a primary signal which is reflected by objects in the surroundings of the radar system as a secondary signal, which secondary signal serves for environment mapping.
Typically, traveling wave tubes are driven with high voltages (1000 Volt or more). These high voltages are generated by the energy supply unit from a low voltage and are provided to the traveling wave tube. The low voltage is provided by the enclosing component (e.g., satellite or radar system). Drops of the high voltage may result from the high load steps (step change in load, sudden load variation) resulting from a sudden variation of the power draw or power input (the required power) when the traveling wave tube is switched on or switched off. Depending on the design of the energy supply unit, a controller unit and an input filter are provided as to keep fluctuations of the high voltage from affecting the low voltage and, hence, from influencing the onboard power system of the enclosing component.
As to keep feedback effects of fluctuations of the high voltage to the low voltage as small as possible, it may be required to provide complex and costly input filters and controllers.